S-99553A447 1/4"-20 x 3/8" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance in harsh environments thanks to 316 Stainless Steel construction, ideal for marine, chemical, and outdoor applications.
• Exceptional thread engagement and holding power with a Class 3A thread fit, ensuring a precise, secure, and vibration-resistant fastening.
• High torque application capability from the 1/8" hex drive and Rockwell B80 hardness, preventing stripping and enabling reliable installation.
• Secure, flush-mount fastening with its headless and oval tip design, minimizing protrusion and preventing component movement.
• Quick and easy installation due to the coarse UNC thread, reducing assembly time in industrial settings.
• Guaranteed reliability and interchangeability as it meets the stringent dimensional requirements of ASME B18.3.
• Safe for sensitive applications with compliance to RoHS 3 and REACH environmental regulations.

Professional Applications & Engineering Value

This 1/4-20 UNC set screw is engineered to solve critical challenges in precision assembly. The 316 Stainless Steel material provides outstanding resistance to corrosion and chemical attack, making it indispensable for equipment in marine, pharmaceutical, and food processing industries where exposure to moisture and aggressive substances is common. Its headless design and oval tip ensure a secure, flush fit that locks components like gears, pulleys, and collars onto shafts without protruding, preventing interference and maintaining alignment. The Class 3A thread fit and coarse thread spacing deliver superior clamping force and vibration resistance, crucial for high-stress mechanical systems. Paired with a 1/8" hex drive for high-torque installation, this screw offers a reliable, long-term fastening solution that reduces maintenance and downtime in demanding industrial applications.

Specification Summary & Compliance

This set screw features a 1/4"-20 UNC thread with a Class 3A fit for high precision and strength. It is manufactured in compliance with ASME B18.3 specifications, ensuring dimensional accuracy and performance. The product is also verified to be RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting strict environmental and safety standards for hazardous substances.